Q.

A conducting circular loop of area1.0 m2 is placed perpendicular to a magnetic field which varies as B=sin(100t) Tesla. If the resistance of the loop is 100 Ω, then the average thermal energy dissipated in the loop in one period is ______ J.      [2026]

1 π2  
2 π  
3 π2  
4 2π  

Ans.

(2)

Area of the loop = 1 m2

B=sin(100t)

  ϕ=BA=sin(100t)

  dϕdt=100cos(100t)

  P=V2R=104cos2(100t)100

  Thermal energy dissipated in 1 time period

          =0TPdt=0T100cos2(100t)dt

           T=2π100=π50 sec

  Q=1000π/50cos2(100t)dt

             =1000π/501+cos(200t)2dt

             =100[π100]=π